My question is, will it hurt the integrity of the material? Our goal is to match it to the concrete coating we had installed next to it (it looks exactly like the decking except darker) and to repel stains. I have to get down on my hands and knees and scrub to remove dirt. I don't have a powerwasher.

I Haven't Tried To Stain A Composite Deck, Id Be Curious To See How It Will Accept The Stain And Whether It Would Be A Splochy Or Not. By Chance If You Have A Few Cut Offs Id Stain Those And See How It Looks.

I Havent Tried To Stain A Composite Deck, Id Be Curious To See How It Will Accept The Stain And Wether It Would Be A Splochy Or Not. By Chance If You Have A Few Cut Offs Id Stain Those And See How It Looks.

glavine, Thank you for you responses. I don't want to stain it... I want to clear seal it, which would make it darker. Here's the situation, we have a concrete slab deck that we enlarged with composite decking. We then hired a company to make the slab look like the decking. We love the sealer they put on the concrete as rain water just beads up and it's so easy to clean. We can see what the sealer will look like on the decking and it brings the two components (decking and concrete) closer together. I can't see why it would hurt the decking, as it doesn't breath anyway, or does it? Can I post a photo here?

Yep... you can post a pic. I haven't found any composite deck material that will accept coatings of any kind. Can't really paint 'em... can't really seal 'em (as far as I know).

Ive Talked To A Composite Sales Rep, I Think It Was For The Timertex Brand, He Said You Could Seal But He Didn't Understand Why Id Want To. But He Seen Nothing Wrong With Doing It. This Has Been A Few Years Ago. If It Don't Work You Can Always Pressure Wash It Off.
As Much As Id Like To Give You A For Sure Answer I Just Say Call The Company And Just Ask Them If It Can Be Done.

Ive Talked To A Composite Sales Rep, I Think It Was For The Timertex Brand, He Said You Could Seal But He Didnt Understand Why Id Want To. But He Seen Nothing Wrong With Doing It. This Has Been A Few Years Ago. If It Dont Work You Can Always Pressure Wash It Off.
As Much As Id Like To Give You A For Sure Answer I Just Say Call The Company And Just Ask Them If It Can Be Done.


This will give you a better idea of what I'm talking about.
http://i9.photobucket.com/albums/a80/DeelyJVD/Misc/IMG_0338.jpg




The concrete slab is in the center and you can see where I wet the composite decking.

That Really Looks Good. I Actually Like The Contrast.

The best deck sealer for cedar deck and redwood deck stains (http://saversystems.com/hardwood.php)

Messmers Composite Wood Deck Stain (http://opwdecks.com/messmerscompositestain.htm)

I've been professionally cleaning and sealing Trex decks for years, mostly due to a mildew problems with some of the colors.
Do not power wash it or you will rough up the finish causing more problems.
I use a deck wash through a pump sprayer. The deck wash I use is Thompsons or Olympic as they kill mildew the best. I due then run it through the injector of the powerwasher which is at a very low pressure and do not go close to the deck. This keeps the soap from drying out and agitates the soap. I then rinse it off and give it a few days of sun to dry out.
I then seal it with a clear all purpose sealer like Cabots. Again sprayed through a pump sprayer with a fan tip. This dries completely clear. It may be a little slippery for a couple of rains but it will stay clean